Work done on a gas as volume decreases

AI Thread Summary
The discussion focuses on calculating the work done on a gas as its volume decreases from infinity to zero, using the pressure function P=e-v2. The work is expressed as dW = PdV, leading to the integral W=∫0∞e-v2dV. The solution references the Gaussian integral, concluding that W=(√∏)/2. Participants seek confirmation on the correctness of this calculation. The conversation emphasizes the application of mathematical principles in physics to derive the work done on the gas.
kabailey
Messages
16
Reaction score
0
In a mathematical model, a gas is under a pressure of the form P=e-v2 (v is volume). Find the work (in Joules) done on the gas as its volume decreases from infinity to zero.



dW = PdV



Solution Attempt:
W=∫0e-v2dV

http://en.wikipedia.org/wiki/Gaussian_integral

Gaussian Integral=∫-∞e-x2dx=√∏

∴∫0e-v2dV

=(√∏)/2|0

W=(√∏)/2

Is this correct?
 
Physics news on Phys.org
anybody?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top